xref: /freebsd/contrib/unbound/util/netevent.c (revision f4b37ed0f8b307b1f3f0f630ca725d68f1dff30d)
1 /*
2  * util/netevent.c - event notification
3  *
4  * Copyright (c) 2007, NLnet Labs. All rights reserved.
5  *
6  * This software is open source.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * Redistributions of source code must retain the above copyright notice,
13  * this list of conditions and the following disclaimer.
14  *
15  * Redistributions in binary form must reproduce the above copyright notice,
16  * this list of conditions and the following disclaimer in the documentation
17  * and/or other materials provided with the distribution.
18  *
19  * Neither the name of the NLNET LABS nor the names of its contributors may
20  * be used to endorse or promote products derived from this software without
21  * specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
24  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
25  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
26  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
27  * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
28  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
29  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
30  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
31  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
32  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
33  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34  */
35 
36 /**
37  * \file
38  *
39  * This file contains event notification functions.
40  */
41 #include "config.h"
42 #include "util/netevent.h"
43 #include "util/log.h"
44 #include "util/net_help.h"
45 #include "util/fptr_wlist.h"
46 #include "ldns/pkthdr.h"
47 #include "ldns/sbuffer.h"
48 #include "dnstap/dnstap.h"
49 #ifdef HAVE_OPENSSL_SSL_H
50 #include <openssl/ssl.h>
51 #endif
52 #ifdef HAVE_OPENSSL_ERR_H
53 #include <openssl/err.h>
54 #endif
55 
56 /* -------- Start of local definitions -------- */
57 /** if CMSG_ALIGN is not defined on this platform, a workaround */
58 #ifndef CMSG_ALIGN
59 #  ifdef _CMSG_DATA_ALIGN
60 #    define CMSG_ALIGN _CMSG_DATA_ALIGN
61 #  else
62 #    define CMSG_ALIGN(len) (((len)+sizeof(long)-1) & ~(sizeof(long)-1))
63 #  endif
64 #endif
65 
66 /** if CMSG_LEN is not defined on this platform, a workaround */
67 #ifndef CMSG_LEN
68 #  define CMSG_LEN(len) (CMSG_ALIGN(sizeof(struct cmsghdr))+(len))
69 #endif
70 
71 /** if CMSG_SPACE is not defined on this platform, a workaround */
72 #ifndef CMSG_SPACE
73 #  ifdef _CMSG_HDR_ALIGN
74 #    define CMSG_SPACE(l) (CMSG_ALIGN(l)+_CMSG_HDR_ALIGN(sizeof(struct cmsghdr)))
75 #  else
76 #    define CMSG_SPACE(l) (CMSG_ALIGN(l)+CMSG_ALIGN(sizeof(struct cmsghdr)))
77 #  endif
78 #endif
79 
80 /** The TCP reading or writing query timeout in seconds */
81 #define TCP_QUERY_TIMEOUT 120
82 
83 #ifndef NONBLOCKING_IS_BROKEN
84 /** number of UDP reads to perform per read indication from select */
85 #define NUM_UDP_PER_SELECT 100
86 #else
87 #define NUM_UDP_PER_SELECT 1
88 #endif
89 
90 /* We define libevent structures here to hide the libevent stuff. */
91 
92 #ifdef USE_MINI_EVENT
93 #  ifdef USE_WINSOCK
94 #    include "util/winsock_event.h"
95 #  else
96 #    include "util/mini_event.h"
97 #  endif /* USE_WINSOCK */
98 #else /* USE_MINI_EVENT */
99    /* we use libevent */
100 #  ifdef HAVE_EVENT_H
101 #    include <event.h>
102 #  else
103 #    include "event2/event.h"
104 #    include "event2/event_struct.h"
105 #    include "event2/event_compat.h"
106 #  endif
107 #endif /* USE_MINI_EVENT */
108 
109 /**
110  * The internal event structure for keeping libevent info for the event.
111  * Possibly other structures (list, tree) this is part of.
112  */
113 struct internal_event {
114 	/** the comm base */
115 	struct comm_base* base;
116 	/** libevent event type, alloced here */
117 	struct event ev;
118 };
119 
120 /**
121  * Internal base structure, so that every thread has its own events.
122  */
123 struct internal_base {
124 	/** libevent event_base type. */
125 	struct event_base* base;
126 	/** seconds time pointer points here */
127 	time_t secs;
128 	/** timeval with current time */
129 	struct timeval now;
130 	/** the event used for slow_accept timeouts */
131 	struct event slow_accept;
132 	/** true if slow_accept is enabled */
133 	int slow_accept_enabled;
134 };
135 
136 /**
137  * Internal timer structure, to store timer event in.
138  */
139 struct internal_timer {
140 	/** the comm base */
141 	struct comm_base* base;
142 	/** libevent event type, alloced here */
143 	struct event ev;
144 	/** is timer enabled */
145 	uint8_t enabled;
146 };
147 
148 /**
149  * Internal signal structure, to store signal event in.
150  */
151 struct internal_signal {
152 	/** libevent event type, alloced here */
153 	struct event ev;
154 	/** next in signal list */
155 	struct internal_signal* next;
156 };
157 
158 /** create a tcp handler with a parent */
159 static struct comm_point* comm_point_create_tcp_handler(
160 	struct comm_base *base, struct comm_point* parent, size_t bufsize,
161         comm_point_callback_t* callback, void* callback_arg);
162 
163 /* -------- End of local definitions -------- */
164 
165 #ifdef USE_MINI_EVENT
166 /** minievent updates the time when it blocks. */
167 #define comm_base_now(x) /* nothing to do */
168 #else /* !USE_MINI_EVENT */
169 /** fillup the time values in the event base */
170 static void
171 comm_base_now(struct comm_base* b)
172 {
173 	if(gettimeofday(&b->eb->now, NULL) < 0) {
174 		log_err("gettimeofday: %s", strerror(errno));
175 	}
176 	b->eb->secs = (time_t)b->eb->now.tv_sec;
177 }
178 #endif /* USE_MINI_EVENT */
179 
180 struct comm_base*
181 comm_base_create(int sigs)
182 {
183 	struct comm_base* b = (struct comm_base*)calloc(1,
184 		sizeof(struct comm_base));
185 	if(!b)
186 		return NULL;
187 	b->eb = (struct internal_base*)calloc(1, sizeof(struct internal_base));
188 	if(!b->eb) {
189 		free(b);
190 		return NULL;
191 	}
192 #ifdef USE_MINI_EVENT
193 	(void)sigs;
194 	/* use mini event time-sharing feature */
195 	b->eb->base = event_init(&b->eb->secs, &b->eb->now);
196 #else
197 #  if defined(HAVE_EV_LOOP) || defined(HAVE_EV_DEFAULT_LOOP)
198 	/* libev */
199 	if(sigs)
200 		b->eb->base=(struct event_base *)ev_default_loop(EVFLAG_AUTO);
201 	else
202 		b->eb->base=(struct event_base *)ev_loop_new(EVFLAG_AUTO);
203 #  else
204 	(void)sigs;
205 #    ifdef HAVE_EVENT_BASE_NEW
206 	b->eb->base = event_base_new();
207 #    else
208 	b->eb->base = event_init();
209 #    endif
210 #  endif
211 #endif
212 	if(!b->eb->base) {
213 		free(b->eb);
214 		free(b);
215 		return NULL;
216 	}
217 	comm_base_now(b);
218 	/* avoid event_get_method call which causes crashes even when
219 	 * not printing, because its result is passed */
220 	verbose(VERB_ALGO,
221 #if defined(HAVE_EV_LOOP) || defined(HAVE_EV_DEFAULT_LOOP)
222 		"libev"
223 #elif defined(USE_MINI_EVENT)
224 		"event "
225 #else
226 		"libevent "
227 #endif
228 		"%s uses %s method.",
229 		event_get_version(),
230 #ifdef HAVE_EVENT_BASE_GET_METHOD
231 		event_base_get_method(b->eb->base)
232 #else
233 		"not_obtainable"
234 #endif
235 	);
236 	return b;
237 }
238 
239 struct comm_base*
240 comm_base_create_event(struct event_base* base)
241 {
242 	struct comm_base* b = (struct comm_base*)calloc(1,
243 		sizeof(struct comm_base));
244 	if(!b)
245 		return NULL;
246 	b->eb = (struct internal_base*)calloc(1, sizeof(struct internal_base));
247 	if(!b->eb) {
248 		free(b);
249 		return NULL;
250 	}
251 	b->eb->base = base;
252 	comm_base_now(b);
253 	return b;
254 }
255 
256 void
257 comm_base_delete(struct comm_base* b)
258 {
259 	if(!b)
260 		return;
261 	if(b->eb->slow_accept_enabled) {
262 		if(event_del(&b->eb->slow_accept) != 0) {
263 			log_err("could not event_del slow_accept");
264 		}
265 	}
266 #ifdef USE_MINI_EVENT
267 	event_base_free(b->eb->base);
268 #elif defined(HAVE_EVENT_BASE_FREE) && defined(HAVE_EVENT_BASE_ONCE)
269 	/* only libevent 1.2+ has it, but in 1.2 it is broken -
270 	   assertion fails on signal handling ev that is not deleted
271  	   in libevent 1.3c (event_base_once appears) this is fixed. */
272 	event_base_free(b->eb->base);
273 #endif /* HAVE_EVENT_BASE_FREE and HAVE_EVENT_BASE_ONCE */
274 	b->eb->base = NULL;
275 	free(b->eb);
276 	free(b);
277 }
278 
279 void
280 comm_base_delete_no_base(struct comm_base* b)
281 {
282 	if(!b)
283 		return;
284 	if(b->eb->slow_accept_enabled) {
285 		if(event_del(&b->eb->slow_accept) != 0) {
286 			log_err("could not event_del slow_accept");
287 		}
288 	}
289 	b->eb->base = NULL;
290 	free(b->eb);
291 	free(b);
292 }
293 
294 void
295 comm_base_timept(struct comm_base* b, time_t** tt, struct timeval** tv)
296 {
297 	*tt = &b->eb->secs;
298 	*tv = &b->eb->now;
299 }
300 
301 void
302 comm_base_dispatch(struct comm_base* b)
303 {
304 	int retval;
305 	retval = event_base_dispatch(b->eb->base);
306 	if(retval != 0) {
307 		fatal_exit("event_dispatch returned error %d, "
308 			"errno is %s", retval, strerror(errno));
309 	}
310 }
311 
312 void comm_base_exit(struct comm_base* b)
313 {
314 	if(event_base_loopexit(b->eb->base, NULL) != 0) {
315 		log_err("Could not loopexit");
316 	}
317 }
318 
319 void comm_base_set_slow_accept_handlers(struct comm_base* b,
320 	void (*stop_acc)(void*), void (*start_acc)(void*), void* arg)
321 {
322 	b->stop_accept = stop_acc;
323 	b->start_accept = start_acc;
324 	b->cb_arg = arg;
325 }
326 
327 struct event_base* comm_base_internal(struct comm_base* b)
328 {
329 	return b->eb->base;
330 }
331 
332 /** see if errno for udp has to be logged or not uses globals */
333 static int
334 udp_send_errno_needs_log(struct sockaddr* addr, socklen_t addrlen)
335 {
336 	/* do not log transient errors (unless high verbosity) */
337 #if defined(ENETUNREACH) || defined(EHOSTDOWN) || defined(EHOSTUNREACH) || defined(ENETDOWN)
338 	switch(errno) {
339 #  ifdef ENETUNREACH
340 		case ENETUNREACH:
341 #  endif
342 #  ifdef EHOSTDOWN
343 		case EHOSTDOWN:
344 #  endif
345 #  ifdef EHOSTUNREACH
346 		case EHOSTUNREACH:
347 #  endif
348 #  ifdef ENETDOWN
349 		case ENETDOWN:
350 #  endif
351 			if(verbosity < VERB_ALGO)
352 				return 0;
353 		default:
354 			break;
355 	}
356 #endif
357 	/* permission denied is gotten for every send if the
358 	 * network is disconnected (on some OS), squelch it */
359 	if(errno == EPERM && verbosity < VERB_DETAIL)
360 		return 0;
361 	/* squelch errors where people deploy AAAA ::ffff:bla for
362 	 * authority servers, which we try for intranets. */
363 	if(errno == EINVAL && addr_is_ip4mapped(
364 		(struct sockaddr_storage*)addr, addrlen) &&
365 		verbosity < VERB_DETAIL)
366 		return 0;
367 	/* SO_BROADCAST sockopt can give access to 255.255.255.255,
368 	 * but a dns cache does not need it. */
369 	if(errno == EACCES && addr_is_broadcast(
370 		(struct sockaddr_storage*)addr, addrlen) &&
371 		verbosity < VERB_DETAIL)
372 		return 0;
373 	return 1;
374 }
375 
376 int tcp_connect_errno_needs_log(struct sockaddr* addr, socklen_t addrlen)
377 {
378 	return udp_send_errno_needs_log(addr, addrlen);
379 }
380 
381 /* send a UDP reply */
382 int
383 comm_point_send_udp_msg(struct comm_point *c, sldns_buffer* packet,
384 	struct sockaddr* addr, socklen_t addrlen)
385 {
386 	ssize_t sent;
387 	log_assert(c->fd != -1);
388 #ifdef UNBOUND_DEBUG
389 	if(sldns_buffer_remaining(packet) == 0)
390 		log_err("error: send empty UDP packet");
391 #endif
392 	log_assert(addr && addrlen > 0);
393 	sent = sendto(c->fd, (void*)sldns_buffer_begin(packet),
394 		sldns_buffer_remaining(packet), 0,
395 		addr, addrlen);
396 	if(sent == -1) {
397 		if(!udp_send_errno_needs_log(addr, addrlen))
398 			return 0;
399 #ifndef USE_WINSOCK
400 		verbose(VERB_OPS, "sendto failed: %s", strerror(errno));
401 #else
402 		verbose(VERB_OPS, "sendto failed: %s",
403 			wsa_strerror(WSAGetLastError()));
404 #endif
405 		log_addr(VERB_OPS, "remote address is",
406 			(struct sockaddr_storage*)addr, addrlen);
407 		return 0;
408 	} else if((size_t)sent != sldns_buffer_remaining(packet)) {
409 		log_err("sent %d in place of %d bytes",
410 			(int)sent, (int)sldns_buffer_remaining(packet));
411 		return 0;
412 	}
413 	return 1;
414 }
415 
416 #if defined(AF_INET6) && defined(IPV6_PKTINFO) && (defined(HAVE_RECVMSG) || defined(HAVE_SENDMSG))
417 /** print debug ancillary info */
418 static void p_ancil(const char* str, struct comm_reply* r)
419 {
420 	if(r->srctype != 4 && r->srctype != 6) {
421 		log_info("%s: unknown srctype %d", str, r->srctype);
422 		return;
423 	}
424 	if(r->srctype == 6) {
425 		char buf[1024];
426 		if(inet_ntop(AF_INET6, &r->pktinfo.v6info.ipi6_addr,
427 			buf, (socklen_t)sizeof(buf)) == 0) {
428 			(void)strlcpy(buf, "(inet_ntop error)", sizeof(buf));
429 		}
430 		buf[sizeof(buf)-1]=0;
431 		log_info("%s: %s %d", str, buf, r->pktinfo.v6info.ipi6_ifindex);
432 	} else if(r->srctype == 4) {
433 #ifdef IP_PKTINFO
434 		char buf1[1024], buf2[1024];
435 		if(inet_ntop(AF_INET, &r->pktinfo.v4info.ipi_addr,
436 			buf1, (socklen_t)sizeof(buf1)) == 0) {
437 			(void)strlcpy(buf1, "(inet_ntop error)", sizeof(buf1));
438 		}
439 		buf1[sizeof(buf1)-1]=0;
440 #ifdef HAVE_STRUCT_IN_PKTINFO_IPI_SPEC_DST
441 		if(inet_ntop(AF_INET, &r->pktinfo.v4info.ipi_spec_dst,
442 			buf2, (socklen_t)sizeof(buf2)) == 0) {
443 			(void)strlcpy(buf2, "(inet_ntop error)", sizeof(buf2));
444 		}
445 		buf2[sizeof(buf2)-1]=0;
446 #else
447 		buf2[0]=0;
448 #endif
449 		log_info("%s: %d %s %s", str, r->pktinfo.v4info.ipi_ifindex,
450 			buf1, buf2);
451 #elif defined(IP_RECVDSTADDR)
452 		char buf1[1024];
453 		if(inet_ntop(AF_INET, &r->pktinfo.v4addr,
454 			buf1, (socklen_t)sizeof(buf1)) == 0) {
455 			(void)strlcpy(buf1, "(inet_ntop error)", sizeof(buf1));
456 		}
457 		buf1[sizeof(buf1)-1]=0;
458 		log_info("%s: %s", str, buf1);
459 #endif /* IP_PKTINFO or PI_RECVDSTDADDR */
460 	}
461 }
462 #endif /* AF_INET6 && IPV6_PKTINFO && HAVE_RECVMSG||HAVE_SENDMSG */
463 
464 /** send a UDP reply over specified interface*/
465 static int
466 comm_point_send_udp_msg_if(struct comm_point *c, sldns_buffer* packet,
467 	struct sockaddr* addr, socklen_t addrlen, struct comm_reply* r)
468 {
469 #if defined(AF_INET6) && defined(IPV6_PKTINFO) && defined(HAVE_SENDMSG)
470 	ssize_t sent;
471 	struct msghdr msg;
472 	struct iovec iov[1];
473 	char control[256];
474 #ifndef S_SPLINT_S
475 	struct cmsghdr *cmsg;
476 #endif /* S_SPLINT_S */
477 
478 	log_assert(c->fd != -1);
479 #ifdef UNBOUND_DEBUG
480 	if(sldns_buffer_remaining(packet) == 0)
481 		log_err("error: send empty UDP packet");
482 #endif
483 	log_assert(addr && addrlen > 0);
484 
485 	msg.msg_name = addr;
486 	msg.msg_namelen = addrlen;
487 	iov[0].iov_base = sldns_buffer_begin(packet);
488 	iov[0].iov_len = sldns_buffer_remaining(packet);
489 	msg.msg_iov = iov;
490 	msg.msg_iovlen = 1;
491 	msg.msg_control = control;
492 #ifndef S_SPLINT_S
493 	msg.msg_controllen = sizeof(control);
494 #endif /* S_SPLINT_S */
495 	msg.msg_flags = 0;
496 
497 #ifndef S_SPLINT_S
498 	cmsg = CMSG_FIRSTHDR(&msg);
499 	if(r->srctype == 4) {
500 #ifdef IP_PKTINFO
501 		msg.msg_controllen = CMSG_SPACE(sizeof(struct in_pktinfo));
502 		log_assert(msg.msg_controllen <= sizeof(control));
503 		cmsg->cmsg_level = IPPROTO_IP;
504 		cmsg->cmsg_type = IP_PKTINFO;
505 		memmove(CMSG_DATA(cmsg), &r->pktinfo.v4info,
506 			sizeof(struct in_pktinfo));
507 		cmsg->cmsg_len = CMSG_LEN(sizeof(struct in_pktinfo));
508 #elif defined(IP_SENDSRCADDR)
509 		msg.msg_controllen = CMSG_SPACE(sizeof(struct in_addr));
510 		log_assert(msg.msg_controllen <= sizeof(control));
511 		cmsg->cmsg_level = IPPROTO_IP;
512 		cmsg->cmsg_type = IP_SENDSRCADDR;
513 		memmove(CMSG_DATA(cmsg), &r->pktinfo.v4addr,
514 			sizeof(struct in_addr));
515 		cmsg->cmsg_len = CMSG_LEN(sizeof(struct in_addr));
516 #else
517 		verbose(VERB_ALGO, "no IP_PKTINFO or IP_SENDSRCADDR");
518 		msg.msg_control = NULL;
519 #endif /* IP_PKTINFO or IP_SENDSRCADDR */
520 	} else if(r->srctype == 6) {
521 		msg.msg_controllen = CMSG_SPACE(sizeof(struct in6_pktinfo));
522 		log_assert(msg.msg_controllen <= sizeof(control));
523 		cmsg->cmsg_level = IPPROTO_IPV6;
524 		cmsg->cmsg_type = IPV6_PKTINFO;
525 		memmove(CMSG_DATA(cmsg), &r->pktinfo.v6info,
526 			sizeof(struct in6_pktinfo));
527 		cmsg->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
528 	} else {
529 		/* try to pass all 0 to use default route */
530 		msg.msg_controllen = CMSG_SPACE(sizeof(struct in6_pktinfo));
531 		log_assert(msg.msg_controllen <= sizeof(control));
532 		cmsg->cmsg_level = IPPROTO_IPV6;
533 		cmsg->cmsg_type = IPV6_PKTINFO;
534 		memset(CMSG_DATA(cmsg), 0, sizeof(struct in6_pktinfo));
535 		cmsg->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
536 	}
537 #endif /* S_SPLINT_S */
538 	if(verbosity >= VERB_ALGO)
539 		p_ancil("send_udp over interface", r);
540 	sent = sendmsg(c->fd, &msg, 0);
541 	if(sent == -1) {
542 		if(!udp_send_errno_needs_log(addr, addrlen))
543 			return 0;
544 		verbose(VERB_OPS, "sendmsg failed: %s", strerror(errno));
545 		log_addr(VERB_OPS, "remote address is",
546 			(struct sockaddr_storage*)addr, addrlen);
547 		return 0;
548 	} else if((size_t)sent != sldns_buffer_remaining(packet)) {
549 		log_err("sent %d in place of %d bytes",
550 			(int)sent, (int)sldns_buffer_remaining(packet));
551 		return 0;
552 	}
553 	return 1;
554 #else
555 	(void)c;
556 	(void)packet;
557 	(void)addr;
558 	(void)addrlen;
559 	(void)r;
560 	log_err("sendmsg: IPV6_PKTINFO not supported");
561 	return 0;
562 #endif /* AF_INET6 && IPV6_PKTINFO && HAVE_SENDMSG */
563 }
564 
565 void
566 comm_point_udp_ancil_callback(int fd, short event, void* arg)
567 {
568 #if defined(AF_INET6) && defined(IPV6_PKTINFO) && defined(HAVE_RECVMSG)
569 	struct comm_reply rep;
570 	struct msghdr msg;
571 	struct iovec iov[1];
572 	ssize_t rcv;
573 	char ancil[256];
574 	int i;
575 #ifndef S_SPLINT_S
576 	struct cmsghdr* cmsg;
577 #endif /* S_SPLINT_S */
578 
579 	rep.c = (struct comm_point*)arg;
580 	log_assert(rep.c->type == comm_udp);
581 
582 	if(!(event&EV_READ))
583 		return;
584 	log_assert(rep.c && rep.c->buffer && rep.c->fd == fd);
585 	comm_base_now(rep.c->ev->base);
586 	for(i=0; i<NUM_UDP_PER_SELECT; i++) {
587 		sldns_buffer_clear(rep.c->buffer);
588 		rep.addrlen = (socklen_t)sizeof(rep.addr);
589 		log_assert(fd != -1);
590 		log_assert(sldns_buffer_remaining(rep.c->buffer) > 0);
591 		msg.msg_name = &rep.addr;
592 		msg.msg_namelen = (socklen_t)sizeof(rep.addr);
593 		iov[0].iov_base = sldns_buffer_begin(rep.c->buffer);
594 		iov[0].iov_len = sldns_buffer_remaining(rep.c->buffer);
595 		msg.msg_iov = iov;
596 		msg.msg_iovlen = 1;
597 		msg.msg_control = ancil;
598 #ifndef S_SPLINT_S
599 		msg.msg_controllen = sizeof(ancil);
600 #endif /* S_SPLINT_S */
601 		msg.msg_flags = 0;
602 		rcv = recvmsg(fd, &msg, 0);
603 		if(rcv == -1) {
604 			if(errno != EAGAIN && errno != EINTR) {
605 				log_err("recvmsg failed: %s", strerror(errno));
606 			}
607 			return;
608 		}
609 		rep.addrlen = msg.msg_namelen;
610 		sldns_buffer_skip(rep.c->buffer, rcv);
611 		sldns_buffer_flip(rep.c->buffer);
612 		rep.srctype = 0;
613 #ifndef S_SPLINT_S
614 		for(cmsg = CMSG_FIRSTHDR(&msg); cmsg != NULL;
615 			cmsg = CMSG_NXTHDR(&msg, cmsg)) {
616 			if( cmsg->cmsg_level == IPPROTO_IPV6 &&
617 				cmsg->cmsg_type == IPV6_PKTINFO) {
618 				rep.srctype = 6;
619 				memmove(&rep.pktinfo.v6info, CMSG_DATA(cmsg),
620 					sizeof(struct in6_pktinfo));
621 				break;
622 #ifdef IP_PKTINFO
623 			} else if( cmsg->cmsg_level == IPPROTO_IP &&
624 				cmsg->cmsg_type == IP_PKTINFO) {
625 				rep.srctype = 4;
626 				memmove(&rep.pktinfo.v4info, CMSG_DATA(cmsg),
627 					sizeof(struct in_pktinfo));
628 				break;
629 #elif defined(IP_RECVDSTADDR)
630 			} else if( cmsg->cmsg_level == IPPROTO_IP &&
631 				cmsg->cmsg_type == IP_RECVDSTADDR) {
632 				rep.srctype = 4;
633 				memmove(&rep.pktinfo.v4addr, CMSG_DATA(cmsg),
634 					sizeof(struct in_addr));
635 				break;
636 #endif /* IP_PKTINFO or IP_RECVDSTADDR */
637 			}
638 		}
639 		if(verbosity >= VERB_ALGO)
640 			p_ancil("receive_udp on interface", &rep);
641 #endif /* S_SPLINT_S */
642 		fptr_ok(fptr_whitelist_comm_point(rep.c->callback));
643 		if((*rep.c->callback)(rep.c, rep.c->cb_arg, NETEVENT_NOERROR, &rep)) {
644 			/* send back immediate reply */
645 			(void)comm_point_send_udp_msg_if(rep.c, rep.c->buffer,
646 				(struct sockaddr*)&rep.addr, rep.addrlen, &rep);
647 		}
648 		if(rep.c->fd == -1) /* commpoint closed */
649 			break;
650 	}
651 #else
652 	(void)fd;
653 	(void)event;
654 	(void)arg;
655 	fatal_exit("recvmsg: No support for IPV6_PKTINFO. "
656 		"Please disable interface-automatic");
657 #endif /* AF_INET6 && IPV6_PKTINFO && HAVE_RECVMSG */
658 }
659 
660 void
661 comm_point_udp_callback(int fd, short event, void* arg)
662 {
663 	struct comm_reply rep;
664 	ssize_t rcv;
665 	int i;
666 
667 	rep.c = (struct comm_point*)arg;
668 	log_assert(rep.c->type == comm_udp);
669 
670 	if(!(event&EV_READ))
671 		return;
672 	log_assert(rep.c && rep.c->buffer && rep.c->fd == fd);
673 	comm_base_now(rep.c->ev->base);
674 	for(i=0; i<NUM_UDP_PER_SELECT; i++) {
675 		sldns_buffer_clear(rep.c->buffer);
676 		rep.addrlen = (socklen_t)sizeof(rep.addr);
677 		log_assert(fd != -1);
678 		log_assert(sldns_buffer_remaining(rep.c->buffer) > 0);
679 		rcv = recvfrom(fd, (void*)sldns_buffer_begin(rep.c->buffer),
680 			sldns_buffer_remaining(rep.c->buffer), 0,
681 			(struct sockaddr*)&rep.addr, &rep.addrlen);
682 		if(rcv == -1) {
683 #ifndef USE_WINSOCK
684 			if(errno != EAGAIN && errno != EINTR)
685 				log_err("recvfrom %d failed: %s",
686 					fd, strerror(errno));
687 #else
688 			if(WSAGetLastError() != WSAEINPROGRESS &&
689 				WSAGetLastError() != WSAECONNRESET &&
690 				WSAGetLastError()!= WSAEWOULDBLOCK)
691 				log_err("recvfrom failed: %s",
692 					wsa_strerror(WSAGetLastError()));
693 #endif
694 			return;
695 		}
696 		sldns_buffer_skip(rep.c->buffer, rcv);
697 		sldns_buffer_flip(rep.c->buffer);
698 		rep.srctype = 0;
699 		fptr_ok(fptr_whitelist_comm_point(rep.c->callback));
700 		if((*rep.c->callback)(rep.c, rep.c->cb_arg, NETEVENT_NOERROR, &rep)) {
701 			/* send back immediate reply */
702 			(void)comm_point_send_udp_msg(rep.c, rep.c->buffer,
703 				(struct sockaddr*)&rep.addr, rep.addrlen);
704 		}
705 		if(rep.c->fd != fd) /* commpoint closed to -1 or reused for
706 		another UDP port. Note rep.c cannot be reused with TCP fd. */
707 			break;
708 	}
709 }
710 
711 /** Use a new tcp handler for new query fd, set to read query */
712 static void
713 setup_tcp_handler(struct comm_point* c, int fd)
714 {
715 	log_assert(c->type == comm_tcp);
716 	log_assert(c->fd == -1);
717 	sldns_buffer_clear(c->buffer);
718 	c->tcp_is_reading = 1;
719 	c->tcp_byte_count = 0;
720 	comm_point_start_listening(c, fd, TCP_QUERY_TIMEOUT);
721 }
722 
723 void comm_base_handle_slow_accept(int ATTR_UNUSED(fd),
724 	short ATTR_UNUSED(event), void* arg)
725 {
726 	struct comm_base* b = (struct comm_base*)arg;
727 	/* timeout for the slow accept, re-enable accepts again */
728 	if(b->start_accept) {
729 		verbose(VERB_ALGO, "wait is over, slow accept disabled");
730 		fptr_ok(fptr_whitelist_start_accept(b->start_accept));
731 		(*b->start_accept)(b->cb_arg);
732 		b->eb->slow_accept_enabled = 0;
733 	}
734 }
735 
736 int comm_point_perform_accept(struct comm_point* c,
737 	struct sockaddr_storage* addr, socklen_t* addrlen)
738 {
739 	int new_fd;
740 	*addrlen = (socklen_t)sizeof(*addr);
741 	new_fd = accept(c->fd, (struct sockaddr*)addr, addrlen);
742 	if(new_fd == -1) {
743 #ifndef USE_WINSOCK
744 		/* EINTR is signal interrupt. others are closed connection. */
745 		if(	errno == EINTR || errno == EAGAIN
746 #ifdef EWOULDBLOCK
747 			|| errno == EWOULDBLOCK
748 #endif
749 #ifdef ECONNABORTED
750 			|| errno == ECONNABORTED
751 #endif
752 #ifdef EPROTO
753 			|| errno == EPROTO
754 #endif /* EPROTO */
755 			)
756 			return -1;
757 #if defined(ENFILE) && defined(EMFILE)
758 		if(errno == ENFILE || errno == EMFILE) {
759 			/* out of file descriptors, likely outside of our
760 			 * control. stop accept() calls for some time */
761 			if(c->ev->base->stop_accept) {
762 				struct comm_base* b = c->ev->base;
763 				struct timeval tv;
764 				verbose(VERB_ALGO, "out of file descriptors: "
765 					"slow accept");
766 				b->eb->slow_accept_enabled = 1;
767 				fptr_ok(fptr_whitelist_stop_accept(
768 					b->stop_accept));
769 				(*b->stop_accept)(b->cb_arg);
770 				/* set timeout, no mallocs */
771 				tv.tv_sec = NETEVENT_SLOW_ACCEPT_TIME/1000;
772 				tv.tv_usec = NETEVENT_SLOW_ACCEPT_TIME%1000;
773 				event_set(&b->eb->slow_accept, -1, EV_TIMEOUT,
774 					comm_base_handle_slow_accept, b);
775 				if(event_base_set(b->eb->base,
776 					&b->eb->slow_accept) != 0) {
777 					/* we do not want to log here, because
778 					 * that would spam the logfiles.
779 					 * error: "event_base_set failed." */
780 				}
781 				if(event_add(&b->eb->slow_accept, &tv) != 0) {
782 					/* we do not want to log here,
783 					 * error: "event_add failed." */
784 				}
785 			}
786 			return -1;
787 		}
788 #endif
789 		log_err_addr("accept failed", strerror(errno), addr, *addrlen);
790 #else /* USE_WINSOCK */
791 		if(WSAGetLastError() == WSAEINPROGRESS ||
792 			WSAGetLastError() == WSAECONNRESET)
793 			return -1;
794 		if(WSAGetLastError() == WSAEWOULDBLOCK) {
795 			winsock_tcp_wouldblock(&c->ev->ev, EV_READ);
796 			return -1;
797 		}
798 		log_err_addr("accept failed", wsa_strerror(WSAGetLastError()),
799 			addr, *addrlen);
800 #endif
801 		return -1;
802 	}
803 	fd_set_nonblock(new_fd);
804 	return new_fd;
805 }
806 
807 #ifdef USE_WINSOCK
808 static long win_bio_cb(BIO *b, int oper, const char* ATTR_UNUSED(argp),
809         int ATTR_UNUSED(argi), long argl, long retvalue)
810 {
811 	verbose(VERB_ALGO, "bio_cb %d, %s %s %s", oper,
812 		(oper&BIO_CB_RETURN)?"return":"before",
813 		(oper&BIO_CB_READ)?"read":((oper&BIO_CB_WRITE)?"write":"other"),
814 		WSAGetLastError()==WSAEWOULDBLOCK?"wsawb":"");
815 	/* on windows, check if previous operation caused EWOULDBLOCK */
816 	if( (oper == (BIO_CB_READ|BIO_CB_RETURN) && argl == 0) ||
817 		(oper == (BIO_CB_GETS|BIO_CB_RETURN) && argl == 0)) {
818 		if(WSAGetLastError() == WSAEWOULDBLOCK)
819 			winsock_tcp_wouldblock((struct event*)
820 				BIO_get_callback_arg(b), EV_READ);
821 	}
822 	if( (oper == (BIO_CB_WRITE|BIO_CB_RETURN) && argl == 0) ||
823 		(oper == (BIO_CB_PUTS|BIO_CB_RETURN) && argl == 0)) {
824 		if(WSAGetLastError() == WSAEWOULDBLOCK)
825 			winsock_tcp_wouldblock((struct event*)
826 				BIO_get_callback_arg(b), EV_WRITE);
827 	}
828 	/* return original return value */
829 	return retvalue;
830 }
831 
832 /** set win bio callbacks for nonblocking operations */
833 void
834 comm_point_tcp_win_bio_cb(struct comm_point* c, void* thessl)
835 {
836 	SSL* ssl = (SSL*)thessl;
837 	/* set them both just in case, but usually they are the same BIO */
838 	BIO_set_callback(SSL_get_rbio(ssl), &win_bio_cb);
839 	BIO_set_callback_arg(SSL_get_rbio(ssl), (char*)&c->ev->ev);
840 	BIO_set_callback(SSL_get_wbio(ssl), &win_bio_cb);
841 	BIO_set_callback_arg(SSL_get_wbio(ssl), (char*)&c->ev->ev);
842 }
843 #endif
844 
845 void
846 comm_point_tcp_accept_callback(int fd, short event, void* arg)
847 {
848 	struct comm_point* c = (struct comm_point*)arg, *c_hdl;
849 	int new_fd;
850 	log_assert(c->type == comm_tcp_accept);
851 	if(!(event & EV_READ)) {
852 		log_info("ignoring tcp accept event %d", (int)event);
853 		return;
854 	}
855 	comm_base_now(c->ev->base);
856 	/* find free tcp handler. */
857 	if(!c->tcp_free) {
858 		log_warn("accepted too many tcp, connections full");
859 		return;
860 	}
861 	/* accept incoming connection. */
862 	c_hdl = c->tcp_free;
863 	log_assert(fd != -1);
864 	new_fd = comm_point_perform_accept(c, &c_hdl->repinfo.addr,
865 		&c_hdl->repinfo.addrlen);
866 	if(new_fd == -1)
867 		return;
868 	if(c->ssl) {
869 		c_hdl->ssl = incoming_ssl_fd(c->ssl, new_fd);
870 		if(!c_hdl->ssl) {
871 			c_hdl->fd = new_fd;
872 			comm_point_close(c_hdl);
873 			return;
874 		}
875 		c_hdl->ssl_shake_state = comm_ssl_shake_read;
876 #ifdef USE_WINSOCK
877 		comm_point_tcp_win_bio_cb(c_hdl, c_hdl->ssl);
878 #endif
879 	}
880 
881 	/* grab the tcp handler buffers */
882 	c->tcp_free = c_hdl->tcp_free;
883 	if(!c->tcp_free) {
884 		/* stop accepting incoming queries for now. */
885 		comm_point_stop_listening(c);
886 	}
887 	/* addr is dropped. Not needed for tcp reply. */
888 	setup_tcp_handler(c_hdl, new_fd);
889 }
890 
891 /** Make tcp handler free for next assignment */
892 static void
893 reclaim_tcp_handler(struct comm_point* c)
894 {
895 	log_assert(c->type == comm_tcp);
896 	if(c->ssl) {
897 #ifdef HAVE_SSL
898 		SSL_shutdown(c->ssl);
899 		SSL_free(c->ssl);
900 		c->ssl = NULL;
901 #endif
902 	}
903 	comm_point_close(c);
904 	if(c->tcp_parent) {
905 		c->tcp_free = c->tcp_parent->tcp_free;
906 		c->tcp_parent->tcp_free = c;
907 		if(!c->tcp_free) {
908 			/* re-enable listening on accept socket */
909 			comm_point_start_listening(c->tcp_parent, -1, -1);
910 		}
911 	}
912 }
913 
914 /** do the callback when writing is done */
915 static void
916 tcp_callback_writer(struct comm_point* c)
917 {
918 	log_assert(c->type == comm_tcp);
919 	sldns_buffer_clear(c->buffer);
920 	if(c->tcp_do_toggle_rw)
921 		c->tcp_is_reading = 1;
922 	c->tcp_byte_count = 0;
923 	/* switch from listening(write) to listening(read) */
924 	comm_point_stop_listening(c);
925 	comm_point_start_listening(c, -1, -1);
926 }
927 
928 /** do the callback when reading is done */
929 static void
930 tcp_callback_reader(struct comm_point* c)
931 {
932 	log_assert(c->type == comm_tcp || c->type == comm_local);
933 	sldns_buffer_flip(c->buffer);
934 	if(c->tcp_do_toggle_rw)
935 		c->tcp_is_reading = 0;
936 	c->tcp_byte_count = 0;
937 	if(c->type == comm_tcp)
938 		comm_point_stop_listening(c);
939 	fptr_ok(fptr_whitelist_comm_point(c->callback));
940 	if( (*c->callback)(c, c->cb_arg, NETEVENT_NOERROR, &c->repinfo) ) {
941 		comm_point_start_listening(c, -1, TCP_QUERY_TIMEOUT);
942 	}
943 }
944 
945 /** continue ssl handshake */
946 #ifdef HAVE_SSL
947 static int
948 ssl_handshake(struct comm_point* c)
949 {
950 	int r;
951 	if(c->ssl_shake_state == comm_ssl_shake_hs_read) {
952 		/* read condition satisfied back to writing */
953 		comm_point_listen_for_rw(c, 1, 1);
954 		c->ssl_shake_state = comm_ssl_shake_none;
955 		return 1;
956 	}
957 	if(c->ssl_shake_state == comm_ssl_shake_hs_write) {
958 		/* write condition satisfied, back to reading */
959 		comm_point_listen_for_rw(c, 1, 0);
960 		c->ssl_shake_state = comm_ssl_shake_none;
961 		return 1;
962 	}
963 
964 	ERR_clear_error();
965 	r = SSL_do_handshake(c->ssl);
966 	if(r != 1) {
967 		int want = SSL_get_error(c->ssl, r);
968 		if(want == SSL_ERROR_WANT_READ) {
969 			if(c->ssl_shake_state == comm_ssl_shake_read)
970 				return 1;
971 			c->ssl_shake_state = comm_ssl_shake_read;
972 			comm_point_listen_for_rw(c, 1, 0);
973 			return 1;
974 		} else if(want == SSL_ERROR_WANT_WRITE) {
975 			if(c->ssl_shake_state == comm_ssl_shake_write)
976 				return 1;
977 			c->ssl_shake_state = comm_ssl_shake_write;
978 			comm_point_listen_for_rw(c, 0, 1);
979 			return 1;
980 		} else if(r == 0) {
981 			return 0; /* closed */
982 		} else if(want == SSL_ERROR_SYSCALL) {
983 			/* SYSCALL and errno==0 means closed uncleanly */
984 			if(errno != 0)
985 				log_err("SSL_handshake syscall: %s",
986 					strerror(errno));
987 			return 0;
988 		} else {
989 			log_crypto_err("ssl handshake failed");
990 			log_addr(1, "ssl handshake failed", &c->repinfo.addr,
991 				c->repinfo.addrlen);
992 			return 0;
993 		}
994 	}
995 	/* this is where peer verification could take place */
996 	log_addr(VERB_ALGO, "SSL DNS connection", &c->repinfo.addr,
997 		c->repinfo.addrlen);
998 
999 	/* setup listen rw correctly */
1000 	if(c->tcp_is_reading) {
1001 		if(c->ssl_shake_state != comm_ssl_shake_read)
1002 			comm_point_listen_for_rw(c, 1, 0);
1003 	} else {
1004 		comm_point_listen_for_rw(c, 1, 1);
1005 	}
1006 	c->ssl_shake_state = comm_ssl_shake_none;
1007 	return 1;
1008 }
1009 #endif /* HAVE_SSL */
1010 
1011 /** ssl read callback on TCP */
1012 static int
1013 ssl_handle_read(struct comm_point* c)
1014 {
1015 #ifdef HAVE_SSL
1016 	int r;
1017 	if(c->ssl_shake_state != comm_ssl_shake_none) {
1018 		if(!ssl_handshake(c))
1019 			return 0;
1020 		if(c->ssl_shake_state != comm_ssl_shake_none)
1021 			return 1;
1022 	}
1023 	if(c->tcp_byte_count < sizeof(uint16_t)) {
1024 		/* read length bytes */
1025 		ERR_clear_error();
1026 		if((r=SSL_read(c->ssl, (void*)sldns_buffer_at(c->buffer,
1027 			c->tcp_byte_count), (int)(sizeof(uint16_t) -
1028 			c->tcp_byte_count))) <= 0) {
1029 			int want = SSL_get_error(c->ssl, r);
1030 			if(want == SSL_ERROR_ZERO_RETURN) {
1031 				return 0; /* shutdown, closed */
1032 			} else if(want == SSL_ERROR_WANT_READ) {
1033 				return 1; /* read more later */
1034 			} else if(want == SSL_ERROR_WANT_WRITE) {
1035 				c->ssl_shake_state = comm_ssl_shake_hs_write;
1036 				comm_point_listen_for_rw(c, 0, 1);
1037 				return 1;
1038 			} else if(want == SSL_ERROR_SYSCALL) {
1039 				if(errno != 0)
1040 					log_err("SSL_read syscall: %s",
1041 						strerror(errno));
1042 				return 0;
1043 			}
1044 			log_crypto_err("could not SSL_read");
1045 			return 0;
1046 		}
1047 		c->tcp_byte_count += r;
1048 		if(c->tcp_byte_count != sizeof(uint16_t))
1049 			return 1;
1050 		if(sldns_buffer_read_u16_at(c->buffer, 0) >
1051 			sldns_buffer_capacity(c->buffer)) {
1052 			verbose(VERB_QUERY, "ssl: dropped larger than buffer");
1053 			return 0;
1054 		}
1055 		sldns_buffer_set_limit(c->buffer,
1056 			sldns_buffer_read_u16_at(c->buffer, 0));
1057 		if(sldns_buffer_limit(c->buffer) < LDNS_HEADER_SIZE) {
1058 			verbose(VERB_QUERY, "ssl: dropped bogus too short.");
1059 			return 0;
1060 		}
1061 		verbose(VERB_ALGO, "Reading ssl tcp query of length %d",
1062 			(int)sldns_buffer_limit(c->buffer));
1063 	}
1064 	log_assert(sldns_buffer_remaining(c->buffer) > 0);
1065 	ERR_clear_error();
1066 	r = SSL_read(c->ssl, (void*)sldns_buffer_current(c->buffer),
1067 		(int)sldns_buffer_remaining(c->buffer));
1068 	if(r <= 0) {
1069 		int want = SSL_get_error(c->ssl, r);
1070 		if(want == SSL_ERROR_ZERO_RETURN) {
1071 			return 0; /* shutdown, closed */
1072 		} else if(want == SSL_ERROR_WANT_READ) {
1073 			return 1; /* read more later */
1074 		} else if(want == SSL_ERROR_WANT_WRITE) {
1075 			c->ssl_shake_state = comm_ssl_shake_hs_write;
1076 			comm_point_listen_for_rw(c, 0, 1);
1077 			return 1;
1078 		} else if(want == SSL_ERROR_SYSCALL) {
1079 			if(errno != 0)
1080 				log_err("SSL_read syscall: %s",
1081 					strerror(errno));
1082 			return 0;
1083 		}
1084 		log_crypto_err("could not SSL_read");
1085 		return 0;
1086 	}
1087 	sldns_buffer_skip(c->buffer, (ssize_t)r);
1088 	if(sldns_buffer_remaining(c->buffer) <= 0) {
1089 		tcp_callback_reader(c);
1090 	}
1091 	return 1;
1092 #else
1093 	(void)c;
1094 	return 0;
1095 #endif /* HAVE_SSL */
1096 }
1097 
1098 /** ssl write callback on TCP */
1099 static int
1100 ssl_handle_write(struct comm_point* c)
1101 {
1102 #ifdef HAVE_SSL
1103 	int r;
1104 	if(c->ssl_shake_state != comm_ssl_shake_none) {
1105 		if(!ssl_handshake(c))
1106 			return 0;
1107 		if(c->ssl_shake_state != comm_ssl_shake_none)
1108 			return 1;
1109 	}
1110 	/* ignore return, if fails we may simply block */
1111 	(void)SSL_set_mode(c->ssl, SSL_MODE_ENABLE_PARTIAL_WRITE);
1112 	if(c->tcp_byte_count < sizeof(uint16_t)) {
1113 		uint16_t len = htons(sldns_buffer_limit(c->buffer));
1114 		ERR_clear_error();
1115 		r = SSL_write(c->ssl,
1116 			(void*)(((uint8_t*)&len)+c->tcp_byte_count),
1117 			(int)(sizeof(uint16_t)-c->tcp_byte_count));
1118 		if(r <= 0) {
1119 			int want = SSL_get_error(c->ssl, r);
1120 			if(want == SSL_ERROR_ZERO_RETURN) {
1121 				return 0; /* closed */
1122 			} else if(want == SSL_ERROR_WANT_READ) {
1123 				c->ssl_shake_state = comm_ssl_shake_read;
1124 				comm_point_listen_for_rw(c, 1, 0);
1125 				return 1; /* wait for read condition */
1126 			} else if(want == SSL_ERROR_WANT_WRITE) {
1127 				return 1; /* write more later */
1128 			} else if(want == SSL_ERROR_SYSCALL) {
1129 				if(errno != 0)
1130 					log_err("SSL_write syscall: %s",
1131 						strerror(errno));
1132 				return 0;
1133 			}
1134 			log_crypto_err("could not SSL_write");
1135 			return 0;
1136 		}
1137 		c->tcp_byte_count += r;
1138 		if(c->tcp_byte_count < sizeof(uint16_t))
1139 			return 1;
1140 		sldns_buffer_set_position(c->buffer, c->tcp_byte_count -
1141 			sizeof(uint16_t));
1142 		if(sldns_buffer_remaining(c->buffer) == 0) {
1143 			tcp_callback_writer(c);
1144 			return 1;
1145 		}
1146 	}
1147 	log_assert(sldns_buffer_remaining(c->buffer) > 0);
1148 	ERR_clear_error();
1149 	r = SSL_write(c->ssl, (void*)sldns_buffer_current(c->buffer),
1150 		(int)sldns_buffer_remaining(c->buffer));
1151 	if(r <= 0) {
1152 		int want = SSL_get_error(c->ssl, r);
1153 		if(want == SSL_ERROR_ZERO_RETURN) {
1154 			return 0; /* closed */
1155 		} else if(want == SSL_ERROR_WANT_READ) {
1156 			c->ssl_shake_state = comm_ssl_shake_read;
1157 			comm_point_listen_for_rw(c, 1, 0);
1158 			return 1; /* wait for read condition */
1159 		} else if(want == SSL_ERROR_WANT_WRITE) {
1160 			return 1; /* write more later */
1161 		} else if(want == SSL_ERROR_SYSCALL) {
1162 			if(errno != 0)
1163 				log_err("SSL_write syscall: %s",
1164 					strerror(errno));
1165 			return 0;
1166 		}
1167 		log_crypto_err("could not SSL_write");
1168 		return 0;
1169 	}
1170 	sldns_buffer_skip(c->buffer, (ssize_t)r);
1171 
1172 	if(sldns_buffer_remaining(c->buffer) == 0) {
1173 		tcp_callback_writer(c);
1174 	}
1175 	return 1;
1176 #else
1177 	(void)c;
1178 	return 0;
1179 #endif /* HAVE_SSL */
1180 }
1181 
1182 /** handle ssl tcp connection with dns contents */
1183 static int
1184 ssl_handle_it(struct comm_point* c)
1185 {
1186 	if(c->tcp_is_reading)
1187 		return ssl_handle_read(c);
1188 	return ssl_handle_write(c);
1189 }
1190 
1191 /** Handle tcp reading callback.
1192  * @param fd: file descriptor of socket.
1193  * @param c: comm point to read from into buffer.
1194  * @param short_ok: if true, very short packets are OK (for comm_local).
1195  * @return: 0 on error
1196  */
1197 static int
1198 comm_point_tcp_handle_read(int fd, struct comm_point* c, int short_ok)
1199 {
1200 	ssize_t r;
1201 	log_assert(c->type == comm_tcp || c->type == comm_local);
1202 	if(c->ssl)
1203 		return ssl_handle_it(c);
1204 	if(!c->tcp_is_reading)
1205 		return 0;
1206 
1207 	log_assert(fd != -1);
1208 	if(c->tcp_byte_count < sizeof(uint16_t)) {
1209 		/* read length bytes */
1210 		r = recv(fd,(void*)sldns_buffer_at(c->buffer,c->tcp_byte_count),
1211 			sizeof(uint16_t)-c->tcp_byte_count, 0);
1212 		if(r == 0)
1213 			return 0;
1214 		else if(r == -1) {
1215 #ifndef USE_WINSOCK
1216 			if(errno == EINTR || errno == EAGAIN)
1217 				return 1;
1218 #ifdef ECONNRESET
1219 			if(errno == ECONNRESET && verbosity < 2)
1220 				return 0; /* silence reset by peer */
1221 #endif
1222 			log_err_addr("read (in tcp s)", strerror(errno),
1223 				&c->repinfo.addr, c->repinfo.addrlen);
1224 #else /* USE_WINSOCK */
1225 			if(WSAGetLastError() == WSAECONNRESET)
1226 				return 0;
1227 			if(WSAGetLastError() == WSAEINPROGRESS)
1228 				return 1;
1229 			if(WSAGetLastError() == WSAEWOULDBLOCK) {
1230 				winsock_tcp_wouldblock(&c->ev->ev, EV_READ);
1231 				return 1;
1232 			}
1233 			log_err_addr("read (in tcp s)",
1234 				wsa_strerror(WSAGetLastError()),
1235 				&c->repinfo.addr, c->repinfo.addrlen);
1236 #endif
1237 			return 0;
1238 		}
1239 		c->tcp_byte_count += r;
1240 		if(c->tcp_byte_count != sizeof(uint16_t))
1241 			return 1;
1242 		if(sldns_buffer_read_u16_at(c->buffer, 0) >
1243 			sldns_buffer_capacity(c->buffer)) {
1244 			verbose(VERB_QUERY, "tcp: dropped larger than buffer");
1245 			return 0;
1246 		}
1247 		sldns_buffer_set_limit(c->buffer,
1248 			sldns_buffer_read_u16_at(c->buffer, 0));
1249 		if(!short_ok &&
1250 			sldns_buffer_limit(c->buffer) < LDNS_HEADER_SIZE) {
1251 			verbose(VERB_QUERY, "tcp: dropped bogus too short.");
1252 			return 0;
1253 		}
1254 		verbose(VERB_ALGO, "Reading tcp query of length %d",
1255 			(int)sldns_buffer_limit(c->buffer));
1256 	}
1257 
1258 	log_assert(sldns_buffer_remaining(c->buffer) > 0);
1259 	r = recv(fd, (void*)sldns_buffer_current(c->buffer),
1260 		sldns_buffer_remaining(c->buffer), 0);
1261 	if(r == 0) {
1262 		return 0;
1263 	} else if(r == -1) {
1264 #ifndef USE_WINSOCK
1265 		if(errno == EINTR || errno == EAGAIN)
1266 			return 1;
1267 		log_err_addr("read (in tcp r)", strerror(errno),
1268 			&c->repinfo.addr, c->repinfo.addrlen);
1269 #else /* USE_WINSOCK */
1270 		if(WSAGetLastError() == WSAECONNRESET)
1271 			return 0;
1272 		if(WSAGetLastError() == WSAEINPROGRESS)
1273 			return 1;
1274 		if(WSAGetLastError() == WSAEWOULDBLOCK) {
1275 			winsock_tcp_wouldblock(&c->ev->ev, EV_READ);
1276 			return 1;
1277 		}
1278 		log_err_addr("read (in tcp r)",
1279 			wsa_strerror(WSAGetLastError()),
1280 			&c->repinfo.addr, c->repinfo.addrlen);
1281 #endif
1282 		return 0;
1283 	}
1284 	sldns_buffer_skip(c->buffer, r);
1285 	if(sldns_buffer_remaining(c->buffer) <= 0) {
1286 		tcp_callback_reader(c);
1287 	}
1288 	return 1;
1289 }
1290 
1291 /**
1292  * Handle tcp writing callback.
1293  * @param fd: file descriptor of socket.
1294  * @param c: comm point to write buffer out of.
1295  * @return: 0 on error
1296  */
1297 static int
1298 comm_point_tcp_handle_write(int fd, struct comm_point* c)
1299 {
1300 	ssize_t r;
1301 	log_assert(c->type == comm_tcp);
1302 	if(c->tcp_is_reading && !c->ssl)
1303 		return 0;
1304 	log_assert(fd != -1);
1305 	if(c->tcp_byte_count == 0 && c->tcp_check_nb_connect) {
1306 		/* check for pending error from nonblocking connect */
1307 		/* from Stevens, unix network programming, vol1, 3rd ed, p450*/
1308 		int error = 0;
1309 		socklen_t len = (socklen_t)sizeof(error);
1310 		if(getsockopt(fd, SOL_SOCKET, SO_ERROR, (void*)&error,
1311 			&len) < 0){
1312 #ifndef USE_WINSOCK
1313 			error = errno; /* on solaris errno is error */
1314 #else /* USE_WINSOCK */
1315 			error = WSAGetLastError();
1316 #endif
1317 		}
1318 #ifndef USE_WINSOCK
1319 #if defined(EINPROGRESS) && defined(EWOULDBLOCK)
1320 		if(error == EINPROGRESS || error == EWOULDBLOCK)
1321 			return 1; /* try again later */
1322 		else
1323 #endif
1324 		if(error != 0 && verbosity < 2)
1325 			return 0; /* silence lots of chatter in the logs */
1326                 else if(error != 0) {
1327 			log_err_addr("tcp connect", strerror(error),
1328 				&c->repinfo.addr, c->repinfo.addrlen);
1329 #else /* USE_WINSOCK */
1330 		/* examine error */
1331 		if(error == WSAEINPROGRESS)
1332 			return 1;
1333 		else if(error == WSAEWOULDBLOCK) {
1334 			winsock_tcp_wouldblock(&c->ev->ev, EV_WRITE);
1335 			return 1;
1336 		} else if(error != 0 && verbosity < 2)
1337 			return 0;
1338 		else if(error != 0) {
1339 			log_err_addr("tcp connect", wsa_strerror(error),
1340 				&c->repinfo.addr, c->repinfo.addrlen);
1341 #endif /* USE_WINSOCK */
1342 			return 0;
1343 		}
1344 	}
1345 	if(c->ssl)
1346 		return ssl_handle_it(c);
1347 
1348 	if(c->tcp_byte_count < sizeof(uint16_t)) {
1349 		uint16_t len = htons(sldns_buffer_limit(c->buffer));
1350 #ifdef HAVE_WRITEV
1351 		struct iovec iov[2];
1352 		iov[0].iov_base = (uint8_t*)&len + c->tcp_byte_count;
1353 		iov[0].iov_len = sizeof(uint16_t) - c->tcp_byte_count;
1354 		iov[1].iov_base = sldns_buffer_begin(c->buffer);
1355 		iov[1].iov_len = sldns_buffer_limit(c->buffer);
1356 		log_assert(iov[0].iov_len > 0);
1357 		log_assert(iov[1].iov_len > 0);
1358 		r = writev(fd, iov, 2);
1359 #else /* HAVE_WRITEV */
1360 		r = send(fd, (void*)(((uint8_t*)&len)+c->tcp_byte_count),
1361 			sizeof(uint16_t)-c->tcp_byte_count, 0);
1362 #endif /* HAVE_WRITEV */
1363 		if(r == -1) {
1364 #ifndef USE_WINSOCK
1365 #  ifdef EPIPE
1366                 	if(errno == EPIPE && verbosity < 2)
1367                         	return 0; /* silence 'broken pipe' */
1368   #endif
1369 			if(errno == EINTR || errno == EAGAIN)
1370 				return 1;
1371 #  ifdef HAVE_WRITEV
1372 			log_err_addr("tcp writev", strerror(errno),
1373 				&c->repinfo.addr, c->repinfo.addrlen);
1374 #  else /* HAVE_WRITEV */
1375 			log_err_addr("tcp send s", strerror(errno),
1376 				&c->repinfo.addr, c->repinfo.addrlen);
1377 #  endif /* HAVE_WRITEV */
1378 #else
1379 			if(WSAGetLastError() == WSAENOTCONN)
1380 				return 1;
1381 			if(WSAGetLastError() == WSAEINPROGRESS)
1382 				return 1;
1383 			if(WSAGetLastError() == WSAEWOULDBLOCK) {
1384 				winsock_tcp_wouldblock(&c->ev->ev, EV_WRITE);
1385 				return 1;
1386 			}
1387 			log_err_addr("tcp send s",
1388 				wsa_strerror(WSAGetLastError()),
1389 				&c->repinfo.addr, c->repinfo.addrlen);
1390 #endif
1391 			return 0;
1392 		}
1393 		c->tcp_byte_count += r;
1394 		if(c->tcp_byte_count < sizeof(uint16_t))
1395 			return 1;
1396 		sldns_buffer_set_position(c->buffer, c->tcp_byte_count -
1397 			sizeof(uint16_t));
1398 		if(sldns_buffer_remaining(c->buffer) == 0) {
1399 			tcp_callback_writer(c);
1400 			return 1;
1401 		}
1402 	}
1403 	log_assert(sldns_buffer_remaining(c->buffer) > 0);
1404 	r = send(fd, (void*)sldns_buffer_current(c->buffer),
1405 		sldns_buffer_remaining(c->buffer), 0);
1406 	if(r == -1) {
1407 #ifndef USE_WINSOCK
1408 		if(errno == EINTR || errno == EAGAIN)
1409 			return 1;
1410 		log_err_addr("tcp send r", strerror(errno),
1411 			&c->repinfo.addr, c->repinfo.addrlen);
1412 #else
1413 		if(WSAGetLastError() == WSAEINPROGRESS)
1414 			return 1;
1415 		if(WSAGetLastError() == WSAEWOULDBLOCK) {
1416 			winsock_tcp_wouldblock(&c->ev->ev, EV_WRITE);
1417 			return 1;
1418 		}
1419 		log_err_addr("tcp send r", wsa_strerror(WSAGetLastError()),
1420 			&c->repinfo.addr, c->repinfo.addrlen);
1421 #endif
1422 		return 0;
1423 	}
1424 	sldns_buffer_skip(c->buffer, r);
1425 
1426 	if(sldns_buffer_remaining(c->buffer) == 0) {
1427 		tcp_callback_writer(c);
1428 	}
1429 
1430 	return 1;
1431 }
1432 
1433 void
1434 comm_point_tcp_handle_callback(int fd, short event, void* arg)
1435 {
1436 	struct comm_point* c = (struct comm_point*)arg;
1437 	log_assert(c->type == comm_tcp);
1438 	comm_base_now(c->ev->base);
1439 
1440 	if(event&EV_READ) {
1441 		if(!comm_point_tcp_handle_read(fd, c, 0)) {
1442 			reclaim_tcp_handler(c);
1443 			if(!c->tcp_do_close) {
1444 				fptr_ok(fptr_whitelist_comm_point(
1445 					c->callback));
1446 				(void)(*c->callback)(c, c->cb_arg,
1447 					NETEVENT_CLOSED, NULL);
1448 			}
1449 		}
1450 		return;
1451 	}
1452 	if(event&EV_WRITE) {
1453 		if(!comm_point_tcp_handle_write(fd, c)) {
1454 			reclaim_tcp_handler(c);
1455 			if(!c->tcp_do_close) {
1456 				fptr_ok(fptr_whitelist_comm_point(
1457 					c->callback));
1458 				(void)(*c->callback)(c, c->cb_arg,
1459 					NETEVENT_CLOSED, NULL);
1460 			}
1461 		}
1462 		return;
1463 	}
1464 	if(event&EV_TIMEOUT) {
1465 		verbose(VERB_QUERY, "tcp took too long, dropped");
1466 		reclaim_tcp_handler(c);
1467 		if(!c->tcp_do_close) {
1468 			fptr_ok(fptr_whitelist_comm_point(c->callback));
1469 			(void)(*c->callback)(c, c->cb_arg,
1470 				NETEVENT_TIMEOUT, NULL);
1471 		}
1472 		return;
1473 	}
1474 	log_err("Ignored event %d for tcphdl.", event);
1475 }
1476 
1477 void comm_point_local_handle_callback(int fd, short event, void* arg)
1478 {
1479 	struct comm_point* c = (struct comm_point*)arg;
1480 	log_assert(c->type == comm_local);
1481 	comm_base_now(c->ev->base);
1482 
1483 	if(event&EV_READ) {
1484 		if(!comm_point_tcp_handle_read(fd, c, 1)) {
1485 			fptr_ok(fptr_whitelist_comm_point(c->callback));
1486 			(void)(*c->callback)(c, c->cb_arg, NETEVENT_CLOSED,
1487 				NULL);
1488 		}
1489 		return;
1490 	}
1491 	log_err("Ignored event %d for localhdl.", event);
1492 }
1493 
1494 void comm_point_raw_handle_callback(int ATTR_UNUSED(fd),
1495 	short event, void* arg)
1496 {
1497 	struct comm_point* c = (struct comm_point*)arg;
1498 	int err = NETEVENT_NOERROR;
1499 	log_assert(c->type == comm_raw);
1500 	comm_base_now(c->ev->base);
1501 
1502 	if(event&EV_TIMEOUT)
1503 		err = NETEVENT_TIMEOUT;
1504 	fptr_ok(fptr_whitelist_comm_point_raw(c->callback));
1505 	(void)(*c->callback)(c, c->cb_arg, err, NULL);
1506 }
1507 
1508 struct comm_point*
1509 comm_point_create_udp(struct comm_base *base, int fd, sldns_buffer* buffer,
1510 	comm_point_callback_t* callback, void* callback_arg)
1511 {
1512 	struct comm_point* c = (struct comm_point*)calloc(1,
1513 		sizeof(struct comm_point));
1514 	short evbits;
1515 	if(!c)
1516 		return NULL;
1517 	c->ev = (struct internal_event*)calloc(1,
1518 		sizeof(struct internal_event));
1519 	if(!c->ev) {
1520 		free(c);
1521 		return NULL;
1522 	}
1523 	c->ev->base = base;
1524 	c->fd = fd;
1525 	c->buffer = buffer;
1526 	c->timeout = NULL;
1527 	c->tcp_is_reading = 0;
1528 	c->tcp_byte_count = 0;
1529 	c->tcp_parent = NULL;
1530 	c->max_tcp_count = 0;
1531 	c->tcp_handlers = NULL;
1532 	c->tcp_free = NULL;
1533 	c->type = comm_udp;
1534 	c->tcp_do_close = 0;
1535 	c->do_not_close = 0;
1536 	c->tcp_do_toggle_rw = 0;
1537 	c->tcp_check_nb_connect = 0;
1538 	c->inuse = 0;
1539 	c->callback = callback;
1540 	c->cb_arg = callback_arg;
1541 	evbits = EV_READ | EV_PERSIST;
1542 	/* libevent stuff */
1543 	event_set(&c->ev->ev, c->fd, evbits, comm_point_udp_callback, c);
1544 	if(event_base_set(base->eb->base, &c->ev->ev) != 0) {
1545 		log_err("could not baseset udp event");
1546 		comm_point_delete(c);
1547 		return NULL;
1548 	}
1549 	if(fd!=-1 && event_add(&c->ev->ev, c->timeout) != 0 ) {
1550 		log_err("could not add udp event");
1551 		comm_point_delete(c);
1552 		return NULL;
1553 	}
1554 	return c;
1555 }
1556 
1557 struct comm_point*
1558 comm_point_create_udp_ancil(struct comm_base *base, int fd,
1559 	sldns_buffer* buffer,
1560 	comm_point_callback_t* callback, void* callback_arg)
1561 {
1562 	struct comm_point* c = (struct comm_point*)calloc(1,
1563 		sizeof(struct comm_point));
1564 	short evbits;
1565 	if(!c)
1566 		return NULL;
1567 	c->ev = (struct internal_event*)calloc(1,
1568 		sizeof(struct internal_event));
1569 	if(!c->ev) {
1570 		free(c);
1571 		return NULL;
1572 	}
1573 	c->ev->base = base;
1574 	c->fd = fd;
1575 	c->buffer = buffer;
1576 	c->timeout = NULL;
1577 	c->tcp_is_reading = 0;
1578 	c->tcp_byte_count = 0;
1579 	c->tcp_parent = NULL;
1580 	c->max_tcp_count = 0;
1581 	c->tcp_handlers = NULL;
1582 	c->tcp_free = NULL;
1583 	c->type = comm_udp;
1584 	c->tcp_do_close = 0;
1585 	c->do_not_close = 0;
1586 	c->inuse = 0;
1587 	c->tcp_do_toggle_rw = 0;
1588 	c->tcp_check_nb_connect = 0;
1589 	c->callback = callback;
1590 	c->cb_arg = callback_arg;
1591 	evbits = EV_READ | EV_PERSIST;
1592 	/* libevent stuff */
1593 	event_set(&c->ev->ev, c->fd, evbits, comm_point_udp_ancil_callback, c);
1594 	if(event_base_set(base->eb->base, &c->ev->ev) != 0) {
1595 		log_err("could not baseset udp event");
1596 		comm_point_delete(c);
1597 		return NULL;
1598 	}
1599 	if(fd!=-1 && event_add(&c->ev->ev, c->timeout) != 0 ) {
1600 		log_err("could not add udp event");
1601 		comm_point_delete(c);
1602 		return NULL;
1603 	}
1604 	return c;
1605 }
1606 
1607 static struct comm_point*
1608 comm_point_create_tcp_handler(struct comm_base *base,
1609 	struct comm_point* parent, size_t bufsize,
1610         comm_point_callback_t* callback, void* callback_arg)
1611 {
1612 	struct comm_point* c = (struct comm_point*)calloc(1,
1613 		sizeof(struct comm_point));
1614 	short evbits;
1615 	if(!c)
1616 		return NULL;
1617 	c->ev = (struct internal_event*)calloc(1,
1618 		sizeof(struct internal_event));
1619 	if(!c->ev) {
1620 		free(c);
1621 		return NULL;
1622 	}
1623 	c->ev->base = base;
1624 	c->fd = -1;
1625 	c->buffer = sldns_buffer_new(bufsize);
1626 	if(!c->buffer) {
1627 		free(c->ev);
1628 		free(c);
1629 		return NULL;
1630 	}
1631 	c->timeout = (struct timeval*)malloc(sizeof(struct timeval));
1632 	if(!c->timeout) {
1633 		sldns_buffer_free(c->buffer);
1634 		free(c->ev);
1635 		free(c);
1636 		return NULL;
1637 	}
1638 	c->tcp_is_reading = 0;
1639 	c->tcp_byte_count = 0;
1640 	c->tcp_parent = parent;
1641 	c->max_tcp_count = 0;
1642 	c->tcp_handlers = NULL;
1643 	c->tcp_free = NULL;
1644 	c->type = comm_tcp;
1645 	c->tcp_do_close = 0;
1646 	c->do_not_close = 0;
1647 	c->tcp_do_toggle_rw = 1;
1648 	c->tcp_check_nb_connect = 0;
1649 	c->repinfo.c = c;
1650 	c->callback = callback;
1651 	c->cb_arg = callback_arg;
1652 	/* add to parent free list */
1653 	c->tcp_free = parent->tcp_free;
1654 	parent->tcp_free = c;
1655 	/* libevent stuff */
1656 	evbits = EV_PERSIST | EV_READ | EV_TIMEOUT;
1657 	event_set(&c->ev->ev, c->fd, evbits, comm_point_tcp_handle_callback, c);
1658 	if(event_base_set(base->eb->base, &c->ev->ev) != 0)
1659 	{
1660 		log_err("could not basetset tcphdl event");
1661 		parent->tcp_free = c->tcp_free;
1662 		free(c->ev);
1663 		free(c);
1664 		return NULL;
1665 	}
1666 	return c;
1667 }
1668 
1669 struct comm_point*
1670 comm_point_create_tcp(struct comm_base *base, int fd, int num, size_t bufsize,
1671         comm_point_callback_t* callback, void* callback_arg)
1672 {
1673 	struct comm_point* c = (struct comm_point*)calloc(1,
1674 		sizeof(struct comm_point));
1675 	short evbits;
1676 	int i;
1677 	/* first allocate the TCP accept listener */
1678 	if(!c)
1679 		return NULL;
1680 	c->ev = (struct internal_event*)calloc(1,
1681 		sizeof(struct internal_event));
1682 	if(!c->ev) {
1683 		free(c);
1684 		return NULL;
1685 	}
1686 	c->ev->base = base;
1687 	c->fd = fd;
1688 	c->buffer = NULL;
1689 	c->timeout = NULL;
1690 	c->tcp_is_reading = 0;
1691 	c->tcp_byte_count = 0;
1692 	c->tcp_parent = NULL;
1693 	c->max_tcp_count = num;
1694 	c->tcp_handlers = (struct comm_point**)calloc((size_t)num,
1695 		sizeof(struct comm_point*));
1696 	if(!c->tcp_handlers) {
1697 		free(c->ev);
1698 		free(c);
1699 		return NULL;
1700 	}
1701 	c->tcp_free = NULL;
1702 	c->type = comm_tcp_accept;
1703 	c->tcp_do_close = 0;
1704 	c->do_not_close = 0;
1705 	c->tcp_do_toggle_rw = 0;
1706 	c->tcp_check_nb_connect = 0;
1707 	c->callback = NULL;
1708 	c->cb_arg = NULL;
1709 	evbits = EV_READ | EV_PERSIST;
1710 	/* libevent stuff */
1711 	event_set(&c->ev->ev, c->fd, evbits, comm_point_tcp_accept_callback, c);
1712 	if(event_base_set(base->eb->base, &c->ev->ev) != 0 ||
1713 		event_add(&c->ev->ev, c->timeout) != 0 )
1714 	{
1715 		log_err("could not add tcpacc event");
1716 		comm_point_delete(c);
1717 		return NULL;
1718 	}
1719 
1720 	/* now prealloc the tcp handlers */
1721 	for(i=0; i<num; i++) {
1722 		c->tcp_handlers[i] = comm_point_create_tcp_handler(base,
1723 			c, bufsize, callback, callback_arg);
1724 		if(!c->tcp_handlers[i]) {
1725 			comm_point_delete(c);
1726 			return NULL;
1727 		}
1728 	}
1729 
1730 	return c;
1731 }
1732 
1733 struct comm_point*
1734 comm_point_create_tcp_out(struct comm_base *base, size_t bufsize,
1735         comm_point_callback_t* callback, void* callback_arg)
1736 {
1737 	struct comm_point* c = (struct comm_point*)calloc(1,
1738 		sizeof(struct comm_point));
1739 	short evbits;
1740 	if(!c)
1741 		return NULL;
1742 	c->ev = (struct internal_event*)calloc(1,
1743 		sizeof(struct internal_event));
1744 	if(!c->ev) {
1745 		free(c);
1746 		return NULL;
1747 	}
1748 	c->ev->base = base;
1749 	c->fd = -1;
1750 	c->buffer = sldns_buffer_new(bufsize);
1751 	if(!c->buffer) {
1752 		free(c->ev);
1753 		free(c);
1754 		return NULL;
1755 	}
1756 	c->timeout = NULL;
1757 	c->tcp_is_reading = 0;
1758 	c->tcp_byte_count = 0;
1759 	c->tcp_parent = NULL;
1760 	c->max_tcp_count = 0;
1761 	c->tcp_handlers = NULL;
1762 	c->tcp_free = NULL;
1763 	c->type = comm_tcp;
1764 	c->tcp_do_close = 0;
1765 	c->do_not_close = 0;
1766 	c->tcp_do_toggle_rw = 1;
1767 	c->tcp_check_nb_connect = 1;
1768 	c->repinfo.c = c;
1769 	c->callback = callback;
1770 	c->cb_arg = callback_arg;
1771 	evbits = EV_PERSIST | EV_WRITE;
1772 	event_set(&c->ev->ev, c->fd, evbits, comm_point_tcp_handle_callback, c);
1773 	if(event_base_set(base->eb->base, &c->ev->ev) != 0)
1774 	{
1775 		log_err("could not basetset tcpout event");
1776 		sldns_buffer_free(c->buffer);
1777 		free(c->ev);
1778 		free(c);
1779 		return NULL;
1780 	}
1781 
1782 	return c;
1783 }
1784 
1785 struct comm_point*
1786 comm_point_create_local(struct comm_base *base, int fd, size_t bufsize,
1787         comm_point_callback_t* callback, void* callback_arg)
1788 {
1789 	struct comm_point* c = (struct comm_point*)calloc(1,
1790 		sizeof(struct comm_point));
1791 	short evbits;
1792 	if(!c)
1793 		return NULL;
1794 	c->ev = (struct internal_event*)calloc(1,
1795 		sizeof(struct internal_event));
1796 	if(!c->ev) {
1797 		free(c);
1798 		return NULL;
1799 	}
1800 	c->ev->base = base;
1801 	c->fd = fd;
1802 	c->buffer = sldns_buffer_new(bufsize);
1803 	if(!c->buffer) {
1804 		free(c->ev);
1805 		free(c);
1806 		return NULL;
1807 	}
1808 	c->timeout = NULL;
1809 	c->tcp_is_reading = 1;
1810 	c->tcp_byte_count = 0;
1811 	c->tcp_parent = NULL;
1812 	c->max_tcp_count = 0;
1813 	c->tcp_handlers = NULL;
1814 	c->tcp_free = NULL;
1815 	c->type = comm_local;
1816 	c->tcp_do_close = 0;
1817 	c->do_not_close = 1;
1818 	c->tcp_do_toggle_rw = 0;
1819 	c->tcp_check_nb_connect = 0;
1820 	c->callback = callback;
1821 	c->cb_arg = callback_arg;
1822 	/* libevent stuff */
1823 	evbits = EV_PERSIST | EV_READ;
1824 	event_set(&c->ev->ev, c->fd, evbits, comm_point_local_handle_callback,
1825 		c);
1826 	if(event_base_set(base->eb->base, &c->ev->ev) != 0 ||
1827 		event_add(&c->ev->ev, c->timeout) != 0 )
1828 	{
1829 		log_err("could not add localhdl event");
1830 		free(c->ev);
1831 		free(c);
1832 		return NULL;
1833 	}
1834 	return c;
1835 }
1836 
1837 struct comm_point*
1838 comm_point_create_raw(struct comm_base* base, int fd, int writing,
1839 	comm_point_callback_t* callback, void* callback_arg)
1840 {
1841 	struct comm_point* c = (struct comm_point*)calloc(1,
1842 		sizeof(struct comm_point));
1843 	short evbits;
1844 	if(!c)
1845 		return NULL;
1846 	c->ev = (struct internal_event*)calloc(1,
1847 		sizeof(struct internal_event));
1848 	if(!c->ev) {
1849 		free(c);
1850 		return NULL;
1851 	}
1852 	c->ev->base = base;
1853 	c->fd = fd;
1854 	c->buffer = NULL;
1855 	c->timeout = NULL;
1856 	c->tcp_is_reading = 0;
1857 	c->tcp_byte_count = 0;
1858 	c->tcp_parent = NULL;
1859 	c->max_tcp_count = 0;
1860 	c->tcp_handlers = NULL;
1861 	c->tcp_free = NULL;
1862 	c->type = comm_raw;
1863 	c->tcp_do_close = 0;
1864 	c->do_not_close = 1;
1865 	c->tcp_do_toggle_rw = 0;
1866 	c->tcp_check_nb_connect = 0;
1867 	c->callback = callback;
1868 	c->cb_arg = callback_arg;
1869 	/* libevent stuff */
1870 	if(writing)
1871 		evbits = EV_PERSIST | EV_WRITE;
1872 	else 	evbits = EV_PERSIST | EV_READ;
1873 	event_set(&c->ev->ev, c->fd, evbits, comm_point_raw_handle_callback,
1874 		c);
1875 	if(event_base_set(base->eb->base, &c->ev->ev) != 0 ||
1876 		event_add(&c->ev->ev, c->timeout) != 0 )
1877 	{
1878 		log_err("could not add rawhdl event");
1879 		free(c->ev);
1880 		free(c);
1881 		return NULL;
1882 	}
1883 	return c;
1884 }
1885 
1886 void
1887 comm_point_close(struct comm_point* c)
1888 {
1889 	if(!c)
1890 		return;
1891 	if(c->fd != -1)
1892 		if(event_del(&c->ev->ev) != 0) {
1893 			log_err("could not event_del on close");
1894 		}
1895 	/* close fd after removing from event lists, or epoll.. is messed up */
1896 	if(c->fd != -1 && !c->do_not_close) {
1897 		verbose(VERB_ALGO, "close fd %d", c->fd);
1898 #ifndef USE_WINSOCK
1899 		close(c->fd);
1900 #else
1901 		closesocket(c->fd);
1902 #endif
1903 	}
1904 	c->fd = -1;
1905 }
1906 
1907 void
1908 comm_point_delete(struct comm_point* c)
1909 {
1910 	if(!c)
1911 		return;
1912 	if(c->type == comm_tcp && c->ssl) {
1913 #ifdef HAVE_SSL
1914 		SSL_shutdown(c->ssl);
1915 		SSL_free(c->ssl);
1916 #endif
1917 	}
1918 	comm_point_close(c);
1919 	if(c->tcp_handlers) {
1920 		int i;
1921 		for(i=0; i<c->max_tcp_count; i++)
1922 			comm_point_delete(c->tcp_handlers[i]);
1923 		free(c->tcp_handlers);
1924 	}
1925 	free(c->timeout);
1926 	if(c->type == comm_tcp || c->type == comm_local)
1927 		sldns_buffer_free(c->buffer);
1928 	free(c->ev);
1929 	free(c);
1930 }
1931 
1932 void
1933 comm_point_send_reply(struct comm_reply *repinfo)
1934 {
1935 	log_assert(repinfo && repinfo->c);
1936 	if(repinfo->c->type == comm_udp) {
1937 		if(repinfo->srctype)
1938 			comm_point_send_udp_msg_if(repinfo->c,
1939 			repinfo->c->buffer, (struct sockaddr*)&repinfo->addr,
1940 			repinfo->addrlen, repinfo);
1941 		else
1942 			comm_point_send_udp_msg(repinfo->c, repinfo->c->buffer,
1943 			(struct sockaddr*)&repinfo->addr, repinfo->addrlen);
1944 #ifdef USE_DNSTAP
1945 		if(repinfo->c->dtenv != NULL &&
1946 		   repinfo->c->dtenv->log_client_response_messages)
1947 			dt_msg_send_client_response(repinfo->c->dtenv,
1948 			&repinfo->addr, repinfo->c->type, repinfo->c->buffer);
1949 #endif
1950 	} else {
1951 #ifdef USE_DNSTAP
1952 		if(repinfo->c->tcp_parent->dtenv != NULL &&
1953 		   repinfo->c->tcp_parent->dtenv->log_client_response_messages)
1954 			dt_msg_send_client_response(repinfo->c->tcp_parent->dtenv,
1955 			&repinfo->addr, repinfo->c->type, repinfo->c->buffer);
1956 #endif
1957 		comm_point_start_listening(repinfo->c, -1, TCP_QUERY_TIMEOUT);
1958 	}
1959 }
1960 
1961 void
1962 comm_point_drop_reply(struct comm_reply* repinfo)
1963 {
1964 	if(!repinfo)
1965 		return;
1966 	log_assert(repinfo && repinfo->c);
1967 	log_assert(repinfo->c->type != comm_tcp_accept);
1968 	if(repinfo->c->type == comm_udp)
1969 		return;
1970 	reclaim_tcp_handler(repinfo->c);
1971 }
1972 
1973 void
1974 comm_point_stop_listening(struct comm_point* c)
1975 {
1976 	verbose(VERB_ALGO, "comm point stop listening %d", c->fd);
1977 	if(event_del(&c->ev->ev) != 0) {
1978 		log_err("event_del error to stoplisten");
1979 	}
1980 }
1981 
1982 void
1983 comm_point_start_listening(struct comm_point* c, int newfd, int sec)
1984 {
1985 	verbose(VERB_ALGO, "comm point start listening %d",
1986 		c->fd==-1?newfd:c->fd);
1987 	if(c->type == comm_tcp_accept && !c->tcp_free) {
1988 		/* no use to start listening no free slots. */
1989 		return;
1990 	}
1991 	if(sec != -1 && sec != 0) {
1992 		if(!c->timeout) {
1993 			c->timeout = (struct timeval*)malloc(sizeof(
1994 				struct timeval));
1995 			if(!c->timeout) {
1996 				log_err("cpsl: malloc failed. No net read.");
1997 				return;
1998 			}
1999 		}
2000 		c->ev->ev.ev_events |= EV_TIMEOUT;
2001 #ifndef S_SPLINT_S /* splint fails on struct timeval. */
2002 		c->timeout->tv_sec = sec;
2003 		c->timeout->tv_usec = 0;
2004 #endif /* S_SPLINT_S */
2005 	}
2006 	if(c->type == comm_tcp) {
2007 		c->ev->ev.ev_events &= ~(EV_READ|EV_WRITE);
2008 		if(c->tcp_is_reading)
2009 			c->ev->ev.ev_events |= EV_READ;
2010 		else	c->ev->ev.ev_events |= EV_WRITE;
2011 	}
2012 	if(newfd != -1) {
2013 		if(c->fd != -1) {
2014 #ifndef USE_WINSOCK
2015 			close(c->fd);
2016 #else
2017 			closesocket(c->fd);
2018 #endif
2019 		}
2020 		c->fd = newfd;
2021 		c->ev->ev.ev_fd = c->fd;
2022 	}
2023 	if(event_add(&c->ev->ev, sec==0?NULL:c->timeout) != 0) {
2024 		log_err("event_add failed. in cpsl.");
2025 	}
2026 }
2027 
2028 void comm_point_listen_for_rw(struct comm_point* c, int rd, int wr)
2029 {
2030 	verbose(VERB_ALGO, "comm point listen_for_rw %d %d", c->fd, wr);
2031 	if(event_del(&c->ev->ev) != 0) {
2032 		log_err("event_del error to cplf");
2033 	}
2034 	c->ev->ev.ev_events &= ~(EV_READ|EV_WRITE);
2035 	if(rd) c->ev->ev.ev_events |= EV_READ;
2036 	if(wr) c->ev->ev.ev_events |= EV_WRITE;
2037 	if(event_add(&c->ev->ev, c->timeout) != 0) {
2038 		log_err("event_add failed. in cplf.");
2039 	}
2040 }
2041 
2042 size_t comm_point_get_mem(struct comm_point* c)
2043 {
2044 	size_t s;
2045 	if(!c)
2046 		return 0;
2047 	s = sizeof(*c) + sizeof(*c->ev);
2048 	if(c->timeout)
2049 		s += sizeof(*c->timeout);
2050 	if(c->type == comm_tcp || c->type == comm_local)
2051 		s += sizeof(*c->buffer) + sldns_buffer_capacity(c->buffer);
2052 	if(c->type == comm_tcp_accept) {
2053 		int i;
2054 		for(i=0; i<c->max_tcp_count; i++)
2055 			s += comm_point_get_mem(c->tcp_handlers[i]);
2056 	}
2057 	return s;
2058 }
2059 
2060 struct comm_timer*
2061 comm_timer_create(struct comm_base* base, void (*cb)(void*), void* cb_arg)
2062 {
2063 	struct comm_timer *tm = (struct comm_timer*)calloc(1,
2064 		sizeof(struct comm_timer));
2065 	if(!tm)
2066 		return NULL;
2067 	tm->ev_timer = (struct internal_timer*)calloc(1,
2068 		sizeof(struct internal_timer));
2069 	if(!tm->ev_timer) {
2070 		log_err("malloc failed");
2071 		free(tm);
2072 		return NULL;
2073 	}
2074 	tm->ev_timer->base = base;
2075 	tm->callback = cb;
2076 	tm->cb_arg = cb_arg;
2077 	event_set(&tm->ev_timer->ev, -1, EV_TIMEOUT,
2078 		comm_timer_callback, tm);
2079 	if(event_base_set(base->eb->base, &tm->ev_timer->ev) != 0) {
2080 		log_err("timer_create: event_base_set failed.");
2081 		free(tm->ev_timer);
2082 		free(tm);
2083 		return NULL;
2084 	}
2085 	return tm;
2086 }
2087 
2088 void
2089 comm_timer_disable(struct comm_timer* timer)
2090 {
2091 	if(!timer)
2092 		return;
2093 	evtimer_del(&timer->ev_timer->ev);
2094 	timer->ev_timer->enabled = 0;
2095 }
2096 
2097 void
2098 comm_timer_set(struct comm_timer* timer, struct timeval* tv)
2099 {
2100 	log_assert(tv);
2101 	if(timer->ev_timer->enabled)
2102 		comm_timer_disable(timer);
2103 	event_set(&timer->ev_timer->ev, -1, EV_TIMEOUT,
2104 		comm_timer_callback, timer);
2105 	if(event_base_set(timer->ev_timer->base->eb->base,
2106 		&timer->ev_timer->ev) != 0)
2107 		log_err("comm_timer_set: set_base failed.");
2108 	if(evtimer_add(&timer->ev_timer->ev, tv) != 0)
2109 		log_err("comm_timer_set: evtimer_add failed.");
2110 	timer->ev_timer->enabled = 1;
2111 }
2112 
2113 void
2114 comm_timer_delete(struct comm_timer* timer)
2115 {
2116 	if(!timer)
2117 		return;
2118 	comm_timer_disable(timer);
2119 	free(timer->ev_timer);
2120 	free(timer);
2121 }
2122 
2123 void
2124 comm_timer_callback(int ATTR_UNUSED(fd), short event, void* arg)
2125 {
2126 	struct comm_timer* tm = (struct comm_timer*)arg;
2127 	if(!(event&EV_TIMEOUT))
2128 		return;
2129 	comm_base_now(tm->ev_timer->base);
2130 	tm->ev_timer->enabled = 0;
2131 	fptr_ok(fptr_whitelist_comm_timer(tm->callback));
2132 	(*tm->callback)(tm->cb_arg);
2133 }
2134 
2135 int
2136 comm_timer_is_set(struct comm_timer* timer)
2137 {
2138 	return (int)timer->ev_timer->enabled;
2139 }
2140 
2141 size_t
2142 comm_timer_get_mem(struct comm_timer* timer)
2143 {
2144 	return sizeof(*timer) + sizeof(struct internal_timer);
2145 }
2146 
2147 struct comm_signal*
2148 comm_signal_create(struct comm_base* base,
2149         void (*callback)(int, void*), void* cb_arg)
2150 {
2151 	struct comm_signal* com = (struct comm_signal*)malloc(
2152 		sizeof(struct comm_signal));
2153 	if(!com) {
2154 		log_err("malloc failed");
2155 		return NULL;
2156 	}
2157 	com->base = base;
2158 	com->callback = callback;
2159 	com->cb_arg = cb_arg;
2160 	com->ev_signal = NULL;
2161 	return com;
2162 }
2163 
2164 void
2165 comm_signal_callback(int sig, short event, void* arg)
2166 {
2167 	struct comm_signal* comsig = (struct comm_signal*)arg;
2168 	if(!(event & EV_SIGNAL))
2169 		return;
2170 	comm_base_now(comsig->base);
2171 	fptr_ok(fptr_whitelist_comm_signal(comsig->callback));
2172 	(*comsig->callback)(sig, comsig->cb_arg);
2173 }
2174 
2175 int
2176 comm_signal_bind(struct comm_signal* comsig, int sig)
2177 {
2178 	struct internal_signal* entry = (struct internal_signal*)calloc(1,
2179 		sizeof(struct internal_signal));
2180 	if(!entry) {
2181 		log_err("malloc failed");
2182 		return 0;
2183 	}
2184 	log_assert(comsig);
2185 	/* add signal event */
2186 	signal_set(&entry->ev, sig, comm_signal_callback, comsig);
2187 	if(event_base_set(comsig->base->eb->base, &entry->ev) != 0) {
2188 		log_err("Could not set signal base");
2189 		free(entry);
2190 		return 0;
2191 	}
2192 	if(signal_add(&entry->ev, NULL) != 0) {
2193 		log_err("Could not add signal handler");
2194 		free(entry);
2195 		return 0;
2196 	}
2197 	/* link into list */
2198 	entry->next = comsig->ev_signal;
2199 	comsig->ev_signal = entry;
2200 	return 1;
2201 }
2202 
2203 void
2204 comm_signal_delete(struct comm_signal* comsig)
2205 {
2206 	struct internal_signal* p, *np;
2207 	if(!comsig)
2208 		return;
2209 	p=comsig->ev_signal;
2210 	while(p) {
2211 		np = p->next;
2212 		signal_del(&p->ev);
2213 		free(p);
2214 		p = np;
2215 	}
2216 	free(comsig);
2217 }
2218